Nitrogen: The bringer of life and death | Hacker News Reader

Nitrogen: The bringer of life and death

bbc.co.uk

53 pointsTurukawa16 comments

We used to make nitrogen triiodide at school. It was a prank explosive. Well it was until we destroyed a whole fume cupboard with it. Blew the glass out.

Nitrogen has eternally had my respect after clearing that mess up.

Make your own (insert disclaimer about this being your problem if you blow yourself up): iodine crystals from eBay/amazon + ammonia concentrate from the same. Mix small amount together, leave to crystallise on a coffee filter. Tickle with a feather or add some jam before it is dry to attact flies (it will blow them up when they land on it). It's relatively safe when wet but the moment it's dry its incredibly unstable.

http://pipeline.corante.com/archives/things_i_wont_work_with...

Note the high percentage of that list which consists of compounds with far too many N-N single bonds. Or double bonds, as some of those compounds seem like someone got in a contest to cram the most azide groups into the smallest space.

I wonder how feasible it would be to use ammonia as fuel? NH3 is liquid, contains no carbon, and releases N2 and water when burned.

Perfectly possible, but I think you'd need about twice as much ammonia as diesel for the same output. Don't quote me on that though... not certain!

This article was a great read, btw.

Also liquid ammonia is cryogenic. Cars would constantly be venting ammonia gas as it boiled off, assuming you didn't want the tanks to explode.

What? Put a cap on the tank. What I mean is you can store ammonia in pressure vessels, same as we do with LPG for cars or barbecues.

Edit: hit update accidentally.

You can't just cap cryogenic materials. As they heat they want to expand.

LNG is _compressed_ not _cooled_. If you're providing _compression_ for a liquid, it can be maintained.

Consider the equivalent: a sealed vessel in which you're boiling water. Eventually it's going to find a weak point. Just because the boiling point here is well below normal ambient temperatures doesn't mean you aren't still getting a 1000:1 expansion ratio from liquid to gas.

And again: venting ammonia is very fraught as it's corrosive and toxic at fairly low concentrations -- it'll burn your lungs off from the inside.

LNG is cooled and compressed to turn it from gas to liquid, and like the bulk cryogenic liquified "fixed gases", it is the cryogenic storage temperature which maintains the liquid state, not the pressure under which it is stored.

This is also true for liquid nitrogen, liquid oxygen, liquid argon & liquid helium.

At ambient temperatures the vapor pressures of these fixed gases are too high for the liquid to be contained by conventional pressure cylinders having tightly shut valves. Instead they are stored cryogenically in highly insulated dewars under low pressures of 35 to 100psi which vent pressures above that to the atmosphere continuously as the liquid slowly evaporates and maintains the reduced temperature of the remaining bulk by self-refrigeration.

That's why these tanks hiss as if they are leaking from the time you have one delivered until the liquid is fully evaporated whether you use it or not.

Carbon dioxide is a different fixed gas since it only has a vapor pressure less than 1000psi at room temperature. So it is available in regular tightly shut welding-style tanks containing 50pounds of liquid at room temperature, or it can be provided as a cryogenic liquid in low-pressure vented dewars like the LN2.

Liquid (anhydrous) ammonia has a vapor pressure less than 1800psi so it can be stored in a tightly shut pressure cylinder itself, stainless steel DOT cylinders are commonly used for lab samples. This is at room temperature, so it is not necessary to be handled cryogenically in order to transport or store ammonia, unlike LNG. As mentioned elsewhere, you wouldn't want to vent ammonia anyway.

And is _tremendously_ poisonous. Fuel leaks or even unburned vapors would be hugely problematic.

The other problem is that you need energy to form ammonia in the first place. Turns out you can use chemical bonds for storage in other compounds as well, including simple hydrocarbon chains forming either gases or liquids. Sabatier process and Fischer-Tropsch process will both create fuels (gas and liquid, respectively), given a hydrogen and carbon feedstock, and input energy.

Turns out the ocean contains a great deal of hydrogen (combined with oxygen as water) and carbon (dissolved as carbonate/bicarbonate and as CO2 gas dissolved in water). And the stuff is really safe to handle and we've been burning it for well over a century.

The US Navy has been researching developing this to industrial scales, and it strikes me as among the better bets I've seen for providing a liquid transportation / mobile use fuel we've got: http://redd.it/22k71x

You know of ammonia as a liquid because it's in solution with water. Anhydrous Ammonia is a gas at atmospheric pressure and is extremely dangerous. We had a 400lb bottle of "pure" ammonia connected to a blue-print machine in the '80's and it was the one thing in the plant I was truly afraid of (we also made and "stuffed" circuit boards and there were plenty of dangerous chemicals around).

Propellants, aka rocket fuel: http://history.nasa.gov/conghand/propelnt.htm

That is not a very good idea. First you would need a pressurized tank. Next every time you fueled up you'd have to don protective gear, goggles for your eyes and heavy rubber gloves.

Anhydrous is without water and seeks it. I worked in the fertilizer business for twenty years. I've seen farmers lose their eyesight from a burst hose and observed some pretty severe burns from it.

It does do a pretty nice job of shrinking a dollar bill by drawing all the moisture out of it. While it definitely is illegal to modify/deface currency this way it's something guys who pumped ammonia did to amuse themselves ;<).

There are already people organized to promote this very idea. Google "ammonia economy" or check out: http://nh3fuelassociation.org/2013/07/02/implementing-an-amm...

Also: https://www.asme.org/engineering-topics/articles/sustainabil...

I know too little of the subject myself to have a position on it, but it is an intriguing idea.

Ammonia was the working fluid in household refrigerators throughout the early 20th century, where it killed lots of people. Freon was invented as a safe replacement for ammonia, and Thomas Midgely was hailed for saving thousands of lives as a result. Albert Einstein invented a new type of refrigerator that didn't use ammonia after hearing of the death of an entire family caused by the explosion of an ammonia refrigerator.

It's still used in commercial refrigeration plants, as it's highly efficient.

Trivium: ammonia is known as R-1. Refrigerant 1. Freon is generally R-12.

Wikipedia thinks it's R-717: http://en.wikipedia.org/wiki/List_of_refrigerants

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